The invention disclosed and claimed herein is generally related to ladders. In particular, the present invention is related to portable ladders for use with inflatable rafts and other small watercraft.
Portable ladders used in connection with small watercraft must be capable of being lowered over the side of the watercraft to a depth beneath the surface of the water that is sufficient to permit their use by a person in the water who wishes to climb into the watercraft. However, if the ladder extends beneath the surface of the water to any significant depth, the ladder is subject to displacement whenever the watercraft is moving through the water, posing problems for the ladder, the watercraft, or both.
Rigid ladders must be either secured to the side of the watercraft or pulled aboard when the watercraft is underway, if damage to the ladder or the watercraft is to be avoided. Either alternative poses disadvantages. If the ladder is secured to the side of the watercraft it is subject to damage by impact with docks or objects in the water. If it is stowed aboard the watercraft, it is not automatically available to a person in the water without assistance, and can be awkward or even impractical to deploy quickly in an emergency.
Simple rope ladders are flexible and thus are not normally damaged as a consequence of motion through the water, nor do they tend to damage the watercraft. However, they tend to twist and become fouled if left overboard while the watercraft is underway and are thus not always immediately available to a person in the water.
White water river rafts pose additional and unique problems. They are subject to violent motion in all directions while in the water, as well as occasional collisions with rocks and other objects. Nevertheless, it is desirable to be able to quickly deploy a ladder overboard when necessary to retrieve a person who has fallen overboard. In white water situations rigid ladders are impractical and even dangerous, and ordinary rope ladders suffer from twisting and fouling, as already noted, and pose the additional danger of entanglement with a person in the water.
Accordingly, it is the object and purpose of the present invention to provide an extendible, self-retracting ladder.
It is a particular object and purpose of the present invention to provide a flexible yet retractable ladder for use with small watercraft such as rafts.
It is yet another object of the present invention to provide a retractable ladder which can be made readily available and immediately extended and deployed overboard when desired, yet which does not interfere with the operation of the watercraft.
It is yet another object of the present invention to provide a retractable ladder which is flexible and can withstand violent water motion, yet which is resistant to twisting or fouling.
Finally, it is an object of the present invention to provide a flexible ladder which can be stowed above the waterline on a watercraft, and yet which can be deployed and used in an emergency by a person in the water without requiring assistance from other persons aboard the watercraft.
These and other objects and purposes are attained in the present invention as described below and defined in the appended claims.